Machine for making spiral pipe



Nov. 3, 1964 E. K. MALKKl ETAL MACHINE FOR MAKING SPIRAL PIPE FiledSept. 13. 1960 FIG.

. gether on the former by United States Patent The invention relates tomachines for making spiral pipe from a continuous strip of material.Machines that enable such articles to be obtained are already known butin these known machines, which always comprise a rotating former, thestrip material is fed into the former at an acute angle with respect tothe axis of the former, the marginal edges of the wound pipe are thenjoined toa seaming means and the completed pipe is advanced axiallyalong the former. Since the strip material has always been fed into theformer at an acute angle to the axis of the former it has hithertoalways been necessary to change the acuteness of this angle to producepipes of different diameters, and owing to this fact, prior art machinesof the aforesaid type must have adjustable strip material guiding meansand seaming means in proper synchronized relation to ensure that thesaid means will always swing perfectly into their adjusted positions.This again results in machines which necessarily are rather complicatedin structure.

This invention has for its object to provide a machine of simplerstructure and greater working reliability than those conventionally usedfor making spiral pipe. The novelty feature of the invention lies in thefact that the machine includes two rollers which bear against each otherand draw strip material fed therebetween at an angle substantially aright angle relative to the axis of said rollers, and a guide meansdisposed around one of said two rollers and providing means such thatthe strip material pushed by the rollers is advanced along the innersurface of said guide means and caused to bend around the said oneroller so that the strip is wound to a helix pitch before being passedby the guide means through the rollers again for seaming. Since therollers also perform the seaming operation the one of the two rollersabout which the strip is not caused to coil carries at one end thereof aseaming member which cooperates with the other roller to perform theseaming operation.

It is advantageous to provide the machine with suitable means foradjusting the pressure with which the rollers bear against the stripmaterial fed therebetween. The length of the rollers correspondapproximately to the width of the strip material in order that the pipemay leave the roller pair at the point where the pipe is formed. This isof importance because it permits the pipe as it is formed to beprojected forwardly in a direction at an angle to the rollers.

The machine of the invention is not restricted to the making of spiralpipe with interlocked seam from a continuous ribbon or strip of metalonly, but the same can be used for making spiral pipe from any materialhaving a certain degree of stiffness, e.g., plastic ribbon, and the seamedges may also be secured together by Welding to provide an overlapjoint or a butt-weld.

The guide means disposed about one of the two rollers consists of a headhaving a guide member which preferably is slightly wider than the seamto be formed and which forms a convolution corresponding to a pitch ofthe helix in which the strip is wound. This guide means may be securedto the machine, e.g., by screw means so that, in end view, the guidemeans and the roller, form circles internally tangent at the pointcommon to the two rollers, and the said guide means begins at one end ofthe roller and ends at the other end of the roller. If a spiral pipewith interlocked seam is to be produced at least the outer edge of theguide member has a suitable guide groove or the like for accommodatingthe up-turned edge provided along one side of the strip, the up-turnededge passing into the guide groove and forcing the strip to bend tohelix pitch as the strip slides between the rollers for seaming. Insofaras a spiral pipe with welded over-lap joint is to be produced at leastthe outer edge of the guide member has a helical shoulder inclinedtoward the roller and forcing the strip to form a convolutioncorresponding to a helix pitch as the strip passes through the rollersand is seamed. Naturally the guide means may be provided with a helicalgroove or slot along the whole length of convolution but such a meanswould be rather hard to make. However, it is not necessary that theguide means be profiled to form a helical element for the main thing isthat the same will form about the one of two rollers a cylindricalsurface which is tangent to said roller at the contact line of the tworollers and is provided with an element which will force the stripissuing from the rollers to bend about the one roller and to form aconvolution corresponding to the pitch of helix in which the strip iswound prior to sealing by second pass through the rollers.

In order that the invention may be clearly understood the invention willnow be described more in detail with reference to the embodiment shownin the accompanying drawings, wherein FIGURE 1 is a face view of amachine of the invention for making spiral pipe with interlocked seam.

FIGURE 2 is a section of the line IIII of FIGURE 1.

FIGURE 3 is a side view of the guide means.

FIGURE 4 is a top view of the machine of the present I invention.

This machine comprises a lower roller 1 and an upper roller 2, whichbear against each other to form a roller pair. The machine has anadjusting screw 3 for adjusting the pressure with which the rollerspress against the strip 4 fed therebetween. The endless strip 4 fromwhich the spiral pipe is made is introduced between the rollers along aline at right angles to the axes of the rollers. Prior to beingintroduced between the rollers, the marginal edges of the strip materialare pro-formed for mechanical interlocking by means known in the art.Along one side of the strip is a turned-up flange 5 and along the otherside of the strip is a folded-over flange 6 with a downwardly openingchannel for the flange 5. The upper roller 2 has at one end a narrowportion of reduced diameter 7 for accommodating the turned-up flange 5and the other end of the said roller is formed by a seaming member 8which cooperates with the lower roller 1 to fold over and pinch theinterengaging marginal edges into lock seam. This seaming member 8 isdetachably by screws 14 or the like secured to the upper roller 2 so thesaid member may be changed for another seaming member when necessary sothat the one and same roller may form an interlocked seam on stripswhich vary in material thickness.

To the machine frame F is secured, by screw means 9, a guide means 19formed by a band of metal slightly wider than the seam to be formed,with a guide member 11 bent around the lower roller 1. It forms aroundthe lower roller a convulution corresponding to the pitch of helix inwhich the strip is wound and begins from the one edge of the stripmerging from between the rollers and after having made a round ends at apoint on the line of contact of the rollers near the other edge of thestrip. To the outer edge of this member is secured by screw means a bar12 so that a helical slot 13 is formed on the one side of the member. Toinitiate the pipe forming operation the front end portion of the stripissuing from and pushed forward by the rollers is bent manually so thatthe turned-up flange 5 along the one edge of the strip resides in theslot 13. When successive portions of the strip are then passed throughthe rollers this slot 13 guides the flange 5 so it will mate in thechannel in the folded-over flange 6 on the other edge of the strip. Thenthe seaming member 8 on the end of the upper roller 2 will cooperatewith the lower roller l to loclt the seam and the pipe begins to takeshape. The seamward-turned end of the lower roller 1, or the left end,as viewed in FIG. 2 and the seaming member end on the upper rollerextend only up to the point at which the seam is formed, but not fartherso as to allow the completed pipe to move obliquely away from therollers immediately after the point where the seam is formed. The slot13 at the end of the guide means provides means such that the strip ontravelling around the roller will always bend a helix pitch amount, andthe guide means itself provides means for producing pipe of desireddiameter. When it is desired to change the pipe diameter, naturally theguide means must be changed for another one which correspond to the newpipe size. The rollers may remain unchanged if the strip width does notchange. Insofar as strip width changes the rollers must be changed tocorrespond to the new strip width.

As is evident from the foregoing description the rollers and the means11, 12 for guiding the strip through the rollers need not be turnablymounted nor in synchronized relation in the machine of the invention,from which it follows that the maclfine of the invention is simpler instructure than the known machines. This, of course, is a notableadvantage.

It is to be understood that the invention is not limited to thehereinabove described embodiment for the same can be modified in manydifferent ways within the scope and spirit of the invention. So, e.g.,the rollers may function also as welding means.

We claim:

1. A machine for forming helical lock seam pipe from elongated stripmaterial having preformed marginal edges providing along one edge of thestrip a straight flange ex tending substantially normal to the strip toone side thereof and along the other edge a folded-over flange forming achannel open to the other side of the strip and adapted to receive saidstraight flange when said helical loch seam is being formed, saidmachine comprising, in combination, a machine frame; a pair of rollersmounted on said frame turnable about substantially parallel axes andspaced from each other so as to be adapted to pull said strip materialfed between said rollers in a direction substantially normal to the axesthereof, one of said rollers being located at the straight flange sideof said strip material and forming between that roller end which facesthe machine frame and said machine frame an annular space for receivingsaid straight flange along one edge of said strip material, the width ofsaid one roller equalling the distance between said preformed marginaledges of said strip material so that said folded-over flange abutsagainst the other end of said one roller; ring-like guide means fixed tosaid machine frame and extending about the other of said rollers, theinner diameter of said guide means substantially equalling the diameterof the pipe to be formed, said guide means having a narrow guide face inform of a single helical convolution of the pipe being formed, saidguide face starting from a point, which when viewed in feed direction ofsaid strip material, is located back of the rollers adjacent to the lineof contact of the rollers near that marginal edge of the strip materialwhich faces the machine frame and terminating at a point, which whenviewed in feed direction, is located in front of the rollers adjacent tothe line of contact of the rollers near the opposite edge of the stripmaterial; short second guide means fixed to and extending along theterminal end of said ring-like guide means and forming with the latter aguide slot for receiving the straight flange ofthe strip materialconvoluted only once about said other roller and guiding said straightflange into the channel formed by the foldedover flange; and anoutwardly widening frusto-conical seam folding means forming anextension of said one roller and cooperating with that portion of theother roller which is adjacent to said frusto-conical seam folding meansfor forcing said folded-over flange with said straight flange locatedtherein against the outer surface of the formed pipe and into a lockseam, said other roller terminating approximately at that point wherethe lock seam is formed so that the finished pipe can leave the machinein a direction obliquely inclined to the roller axes.

2. A machine as set forth in claim 1 in which said ringlike guide meansis formed from a metal plate formed with a hole therethroughcorresponding to the outer diameter of the pipe to be formed, said metalplate being cut open from one edge thereof and bent so that the edgeface of said hole extends along one convolution of the helix of the pipeto be formed.

3. A machine for forming helical lock seam pipe from strip material of apreselected width and having preformed marginal edges providing alongone edge of the strip a straight flange extending substantially normalto the strip to one side thereof and along the other edge a folded-overflange forming a channel open to the other side of the strip, saidmachine comprising, in combination, a support; a pair of rollers mountedon said support turnable about substantially parallel axes and spacedfrom each other so as to be adapted to engage elongated strip materialfed between said rollers on opposite face portions thereof and to feedsaid strip in a direction substantially normal to said axes, one of saidrollers having a width substantially equal to said preselected width;first stationary, narrow and continuous guide means fixed to saidsupport and extending in form of a convolution having a pitch anglesubstantially equal to that of the helix of the pipe to be formed aboutthe other of said rollers from the region of one to the region of theother end of said one roller and having an inner surface located along acylinder having a diameter substantially equal to the outer diameter ofthe pipe to be formed for engaging surface portions of said stripopposite to those engaged by said one roller for bending said stripwhile the strip is fed by said rollers, said first guide means having ahelical side guide face engaging one side of said straight flange;second stationary elongated guide means extending only along a portionof said side guide face in the region in which said side guide faceapproaches said other end of said one roller for gripping said strip atsaid straight flange thereof during feeding of said strip by saidrollers so as to coil said strip into a helix and for guiding saidstraight flange at one edge of the convoluted strip portion into theopen end of the channel formed by the folded-over flange on the otheredge of successive strip portions fed between said rollers, said secondstationary guide means being fixed to said first stationary guide meansspaced therefrom and extending substantially parallel thereto so as todefine with said helical side guide face a gap of a width substantiallyequal to the thickness of said straight flange; and roller means fixedto said other end of said one roller for rotation therewith about itsaxis and cooperating with one end of said other roller for folding saidfolded-over flange with said straight flange located therein into a lockseam, said other roller having a width substantially equal to thecombined width of said one roller and said roller means so that thefinished pipe can leave the machine obliquely inclined to the axes ofsaid rollers.

References Cited in the file of this patent UNITED STATES PATENTS519,182 Gould May 1, 1894 1,394,116 Rendavo Oct. 18, 1921 2,136,942Freeze Nov. 15, 1938 2,136,943 Freeze Nov. 15, 1938 2,282,176 Fay et a1.May 5, 1942 2,635,572 Hesterman Apr. 21, 1953

1. A MACHINE FOR FORMING HELICAL LOCK SEAM PIPE FROM ELONGATED STRIPMATERIAL HAVING PREFORMED MARGINAL EDGES PROVIDING ALONG ONE EDGE OF THESTRIP A STRAIGHT FLANGE EXTENDING SUBSTANTIALLY NORMAL TO THE STRIP TOONE SIDE THEREOF AND ALONG THE OTHER EDGE A FOLDED-OVER FLANGE FORMING ACHANNEL OPEN TO THE OTHER SIDE OF THE STRIP AND ADAPTED TO RECEIVE SAIDSTRAIGHT FLANGE WHEN SAID HELICAL LOCK SEAM IS BEING FORMED, SAIDMACHINE COMPRISING, IN COMBINATION, A MACHINE FRAME; A PAIR OF ROLLERSMOUNTED ON SAID FRAME TURNABLE ABOUT SUBSTANTIALLY PARALLEL AXES ANDSPACED FROM EACH OTHER SO AS TO BE ADAPTED TO PULL SAID STRIP MATERIALFED BETWEEN SAID ROLLERS IN A DIRECTION SUBSTANTIALLY NORMAL TO THE AXESTHEREOF, ONE OF SAID ROLLERS BEING LOCATED AT THE STRAIGHT FLANGE SIDEOF SAID STRIP MATERIAL AND FORMING BETWEEN THAT ROLLER END WHICH FACESTHE MACHINE FRAME AND SAID MACHINE FRAME AND ANNULAR SPACE FOR RECEIVINGSAID STRAIGHT FLANGE ALONG ONE EDGE OF SAID STRIP MATERIAL, THE WIDTH OFSAID ONE ROLLER EQUALLING THE DISTANCE BETWEEN SAID PREFORMED MARGINALEDGES OF SAID STRIP MATERIAL SO THAT SAID FOLDED-OVER FLANGE ABUTSAGAINST THE OTHER END OF SAID ONE ROLLER; RING-LIKE GUIDE MEANS FIXED TOSAID MACHINE FRAME AND EXTENDING ABOUT THE OTHER OF SAID ROLLERS, THEINNER DIAMETER OF SAID GUIDE MEANS SUBSTANTIALLY EQUALLING THE DIAMETEROF THE PIPE TO BE FORMED, SAID GUIDE MEANS HAVING A NARROW GUIDE FACE INFORM OF A SINGLE HELICAL CONVOLUTION OF THE PIPE BEING FORMED, SAIDGUIDE FACE STARTING FROM A POINT, WHICH WHEN VIEWED IN FEED DIRECTION OFSAID STRIP MATERIAL, IS LOCATED BACK OF THE ROLLERS ADJACENT TO THE LINEOF CONTACT OF THE ROLLERS NEAR THAT MARGINAL EDGE OF THE STRIP MATERIALWHICH FACES THE MACHINE FRAME AND TERMINATING AT A POINT, WHICH WHENVIEWED IN FEED DIRECTION, IS LOCATED IN FRONT OF THE ROLLERS ADJACENT TOTHE LINE OF CONTACT OF THE ROLLERS NEAR THE OPPOSITE EDGE OF THE STRIPMATERIAL; SHORT SECOND GUIDE MEANS FIXED TO AND EXTENDING ALONG THETERMINAL END OF SAID RING-LIKE GUIDE MEANS AND FORMING WITH THE LATTER AGUIDE SLOT FOR RECEIVING THE STRAIGHT FLANGE OF THE STRIP MATERIALCONVOLUTED ONLY ONCE ABOUT SAID OTHER ROLLER AND GUIDING SAID STRAIGHTFLANGE INTO THE CHANNEL FORMED BY THE FOLDEDOVER FLANGE; AND ANOUTWARDLY WIDENING FRUSTO-CONICAL SEAM FOLDING MEANS FORMING ANEXTENSION OF SAID ONE ROLLER AND COOPERATING WITH THAT PORTION OF THEOTHER ROLLER WHICH IS ADJACENT TO SAID FRUSTO-CONICAL SEAM FOLDING MEANSFOR FORCING SAID FOLDED-OVER FLANGE WITH SAID STRAIGHT FLANGE LOCATEDTHEREIN AGAINST THE OUTER SURFACE OF THE FORMED PIPE AND INTO A LOCKSEAM, SAID OTHER ROLLER TERMINATING APPROXIMATELY AT THAT POINT WHERETHE LOCK SEAM IS FORMED SO THAT THE FINISHED PIPE CAN LEAVE THE MACHINEIN A DIRECTION OBLIQUELY INCLINED TO THE ROLLER AXES.